2011 ASA/ACCF/AHA/AANN/AANS/ACR/ASNR/CNS/SAIP/SCAI/SIR/SNIS/SVM/SVS guideline on the management of patients with extracranial carotid and vertebral artery disease: Executive summary: A report of the American college of cardiology foundation/american heart association task force on practice guidelines, and the American stroke association, American association of neuroscience nurses

HomeCirculationVol. 124, No. 42011 ASA/ACCF/AHA/AANN/AANS/ACR/ASNR/CNS/SAIP/SCAI/SIR/SNIS/SVM/SVS Guideline on the Management of Patients With Extracranial Carotid and Vertebral Artery Disease: Executive Summary Free AccessResearch ArticlePDF/EPUBAboutView PDFView EPUBSections ToolsAdd to favoritesDownload citationsTrack citationsPermissions ShareShare onFacebookTwitterLinked InMendeleyReddit Jump toFree AccessResearch ArticlePDF/EPUB2011 ASA/ACCF/AHA/AANN/AANS/ACR/ASNR/CNS/SAIP/SCAI/SIR/SNIS/SVM/SVS Guideline on the Management of Patients With Extracranial Carotid and Vertebral Artery Disease: Executive SummaryA Report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines, and the American Stroke Association, American Association of Neuroscience Nurses, American Association of Neurological Surgeons, American College of Radiology, American Society of Neuroradiology, Congress of Neurological Surgeons, Society of Atherosclerosis Imaging and Prevention, Society for Cardiovascular Angiography and Interventions, Society of Interventional Radiology, Society of NeuroInterventional Surgery, Society for Vascular Medicine, and Society for Vascular Surgery Thomas G. Brott, MD, Jonathan L. Halperin, MD, Suhny Abbara, MD, J. Michael Bacharach, MD, John D. Barr, MD, Ruth L. Bush, MD, MPH, Christopher U. Cates, MD, Mark A. Creager, MD, Susan B. Fowler, PhD, Gary Friday, MD, Vicki S. Hertzberg, PhD, E. Bruce McIff, MD, Wesley S. Moore, MD, Peter D. Panagos, MD, Thomas S. Riles, MD, Robert H. Rosenwasser, MD and Allen J. Taylor, MD Thomas G. BrottThomas G. Brott *, †, ‡, §, ‖, , #, **, ††, ‡‡, §§, ‖ ‖, , ##, *** Search for more papers by this author , Jonathan L. HalperinJonathan L. Halperin *, †, ‡, §, ‖, , #, **, ††, ‡‡, §§, ‖ ‖, , ##, *** Search for more papers by this author , Suhny AbbaraSuhny Abbara *, †, ‡, §, ‖, , #, **, ††, ‡‡, §§, ‖ ‖, , ##, *** Search for more papers by this author , J. Michael BacharachJ. Michael Bacharach *, †, ‡, §, ‖, , #, **, ††, ‡‡, §§, ‖ ‖, , ##, *** Search for more papers by this author , John D. BarrJohn D. Barr *, †, ‡, §, ‖, , #, **, ††, ‡‡, §§, ‖ ‖, , ##, *** Search for more papers by this author , Ruth L. BushRuth L. Bush Search for more papers by this author , Christopher U. CatesChristopher U. Cates *, †, ‡, §, ‖, , #, **, ††, ‡‡, §§, ‖ ‖, , ##, *** Search for more papers by this author , Mark A. CreagerMark A. Creager *, †, ‡, §, ‖, , #, **, ††, ‡‡, §§, ‖ ‖, , ##, *** Search for more papers by this author , Susan B. FowlerSusan B. Fowler *, †, ‡, §, ‖, , #, **, ††, ‡‡, §§, ‖ ‖, , ##, *** Search for more papers by this author , Gary FridayGary Friday *, †, ‡, §, ‖, , #, **, ††, ‡‡, §§, ‖ ‖, , ##, *** Search for more papers by this author , Vicki S. HertzbergVicki S. Hertzberg Search for more papers by this author , E. Bruce McIffE. Bruce McIff *, †, ‡, §, ‖, , #, **, ††, ‡‡, §§, ‖ ‖, , ##, *** Search for more papers by this author , Wesley S. MooreWesley S. Moore Search for more papers by this author , Peter D. PanagosPeter D. Panagos *, †, ‡, §, ‖, , #, **, ††, ‡‡, §§, ‖ ‖, , ##, *** Search for more papers by this author , Thomas S. RilesThomas S. Riles *, †, ‡, §, ‖, , #, **, ††, ‡‡, §§, ‖ ‖, , ##, *** Search for more papers by this author , Robert H. RosenwasserRobert H. Rosenwasser *, †, ‡, §, ‖, , #, **, ††, ‡‡, §§, ‖ ‖, , ##, *** Search for more papers by this author and Allen J. TaylorAllen J. Taylor *, †, ‡, §, ‖, , #, **, ††, ‡‡, §§, ‖ ‖, , ##, *** Search for more papers by this author Originally published31 Jan 2011https://doi.org/10.1161/CIR.0b013e31820d8d78Circulation. 2011;124:489–532is corrected byCorrectionCorrectionOther version(s) of this articleYou are viewing the most recent version of this article. Previous versions: January 1, 2011: Previous Version 1 Table of ContentsPreamble . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .491 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .493 1.1 Methodology and Evidence Review . . . . . . . . .4931.2 Organization of the Writing Committee . . . . . .4941.3 Document Review and Approval . . . . . . . . . . .494Recommendations for Duplex Ultrasonography to Evaluate Asymptomatic Patients With Known or Suspected Carotid Stenosis . . . . . . . . . . . . . . . . .494Recommendations for Diagnostic Testing in Patients With Symptoms or Signs of Extracranial Carotid Artery Disease . . . . . . . . . . . . .495Recommendations for the Treatment of Hypertension . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .495Recommendation for Cessation of Tobacco Smoking. . . . . . . . . . . . . . . . . . . . . . . . . . .495Recommendations for Control of Hyperlipidemia. . . . . . . . . . . . . . . . . . . . . . . . . . . . .496Recommendations for Management of Diabetes Mellitus in Patients With Atherosclerosis of the Extracranial Carotid or Vertebral Arteries. . . . . . . . . . . . . . . . . . . . . . . . . . .496Recommendations for Antithrombotic Therapy in Patients With Extracranial Carotid Atherosclerotic Disease Not Undergoing Revascularization . . . . . . . . . . . . . . . . . . . . . . . . . . .496Recommendations for Selection of Patients for Carotid Revascularization . . . . . . . . . . . . . . . . . .497Recommendations for Periprocedural Management of Patients Undergoing Carotid Endarterectomy. . . . . . . . . . . . . . . . . . . . . . . . . . . . .497Recommendations for Management of Patients Undergoing Carotid Artery Stenting. . . . . . . . . . . . .498Recommendations for Management of Patients Experiencing Restenosis After Carotid Endarterectomy or Stenting . . . . . . . . . . . . . . . . . . .498Recommendations for Vascular Imaging in Patients With Vertebral Artery Disease . . . . . . . . . .498Recommendations for Management of Atherosclerotic Risk Factors in Patients With Vertebral Artery Disease . . . . . . . . . . . . . . . . . . . . .499Recommendations for the Management of Patients With Occlusive Disease of the Subclavian and Brachiocephalic Arteries . . . . . . . . . . . . . . . . . .499Recommendations for Carotid Artery Evaluation and Revascularization Before Cardiac Surgery . . . . . . . . . . . . . . . . . . . . . . . . . . . .499Recommendations for Management of Patients With Fibromuscular Dysplasia of the Extracranial Carotid Arteries . . . . . . . . . . . . . . . . . .499Recommendations for Management of Patients With Cervical Artery Dissection. . . . . . . . . . . . . . . .500Cerebrovascular Arterial Anatomy . . . . . . . . . . . . . .500 19.1 Epidemiology of Extracranial Cerebrovascular Disease and Stroke . . . . . . . .500Atherosclerotic Disease of the Extracranial Carotid and Vertebral Arteries . . . . . . . . . . . . . . . . .500Clinical Presentation. . . . . . . . . . . . . . . . . . . . . . . . .500Clinical Assessment of Patients With Focal Cerebral Ischemic Symptoms . . . . . . . . . . . . . . . . . .501Diagnosis and Testing . . . . . . . . . . . . . . . . . . . . . . .503Medical Therapy for Patients With Atherosclerotic Disease of the Extracranial Carotid or Vertebral Arteries . . . . . . . . . . . . . . . . . .504 24.1 Risk Factor Management . . . . . . . . . . . . . . . .50424.2 Antithrombotic Therapy . . . . . . . . . . . . . . . . .50524.3 Carotid Endarterectomy. . . . . . . . . . . . . . . . . .505 24.3.1 Symptomatic Patients . . . . . . . . . . . . .50524.3.2 Asymptomatic Patients . . . . . . . . . . . .50624.4 Carotid Artery Stenting. . . . . . . . . . . . . . . . . .50624.5 Comparative Assessment of Carotid Endarterectomy and Stenting . . . . . . . . . . . . .512 24.5.1 Selection of Carotid Endarterectomy or Carotid Artery Stenting for Individual Patients With Carotid Stenosis . . . . . . . . . . . . . . . . .51424.6 Durability of Carotid Revascularization . . . . .514Vertebral Artery Disease . . . . . . . . . . . . . . . . . . . . .514 25.1 Anatomy of the Vertebrobasilar Arterial Circulation . . . . . . . . . . . . . . . . . . . . .51425.2 Epidemiology of Vertebral Artery Disease . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51525.3 Clinical Presentation of Patients With Vertebrobasilar Arterial Insufficiency . . . . . . .51525.4 Evaluation of Patients With Vertebral Artery Disease . . . . . . . . . . . . . . . . . . . . . . . .51525.5 Medical Therapy of Patients With Vertebral Artery Disease . . . . . . . . . . . . . . . . . . . . . . . .51525.6 Vertebral Artery Revascularization . . . . . . . . .515Diseases of the Subclavian and Brachiocephalic Arteries. . . . . . . . . . . . . . . . . . . . . .515 26.1 Revascularization of the Brachiocephalic and Subclavian Arteries . . . . . . . . . . . . . . . . .516Special Populations . . . . . . . . . . . . . . . . . . . . . . . . .516 27.1 Neurological Risk Reduction in Patients With Carotid Artery Disease Undergoing Cardiac Surgery . . . . . . . . . . . . . . . . . . . . . . .516Nonatherosclerotic Carotid and Vertebral Artery Diseases . . . . . . . . . . . . . . . . . . . . . . . . . . . .516 28.1 Fibromuscular Dysplasia . . . . . . . . . . . . . . . . .51628.2 Cervical Artery Dissection . . . . . . . . . . . . . . .51728.3 Future Research . . . . . . . . . . . . . . . . . . . . . . . . . . . .517References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .518Appendix 1. Author Relationships With Industry and Other Entities . . . . . . . . . . . . . . . . . . .526Appendix 2. Reviewer Relationships With Industry and Other Entities . . . . . . . . . . . . . . . . . . .528Jacobs Alice K., MD, FACC, FAHAChair, ACCF/AHA Task Force on Practice GuidelinesSmith Sidney C., MD, FACC, FAHAImmediate Past Chair, ACCF/AHA Task Force on Practice GuidelinesPreambleIt is essential that the medical profession play a central role in critically evaluating the evidence related to drugs, devices, and procedures for the detection, management, or prevention of disease. Properly applied, rigorous, expert analysis of the available data documenting absolute and relative benefits and risks of these therapies and procedures can improve the effectiveness of care, optimize patient outcomes, and favorably affect the cost of care by focusing resources on the most effective strategies. One important use of such data is the production of clinical practice guidelines that, in turn, can provide a foundation for a variety of other applications such as performance measures, appropriate use criteria, clinical decision support tools, and quality improvement tools.The American College of Cardiology Foundation (ACCF) and the American Heart Association (AHA) have jointly engaged in the production of guidelines in the area of cardiovascular disease since 1980. The ACCF/AHA Task Force on Practice Guidelines (Task Force) is charged with developing, updating, and revising practice guidelines for cardiovascular diseases and procedures, and the Task Force directs and oversees this effort. Writing committees are charged with assessing the evidence as an independent group of authors to develop, update, or revise recommendations for clinical practice.Experts in the subject under consideration have been selected from both organizations to examine subject-specific data and write guidelines in partnership with representatives from other medical practitioner and specialty groups. Writing committees are specifically charged to perform a formal literature review; weigh the strength of evidence for or against particular tests, treatments, or procedures; and include estimates of expected health outcomes where data exist. Patient-specific modifiers, comorbidities, and issues of patient preference that may influence the choice of tests or therapies are considered. When available, information from studies on cost is considered, but data on efficacy and clinical outcomes constitute the primary basis for recommendations in these guidelines.In analyzing the data and developing the recommendations and supporting text, the writing committee used evidence-based methodologies developed by the Task Force that are described elsewhere.1 The committee reviewed and ranked evidence supporting current recommendations with the weight of evidence ranked as Level A if the data were derived from multiple randomized clinical trials or meta-analyses. The committee ranked available evidence as Level B when data were derived from a single randomized trial or nonrandomized studies. Evidence was ranked as Level C when the primary source of the recommendation was consensus opinion, case studies, or standard of care. In the narrative portions of these guidelines, evidence is generally presented in chronological order of development. Studies are identified as observational, retrospective, prospective, or randomized when appropriate. For certain conditions for which inadequate data are available, recommendations are based on expert consensus and clinical experience and ranked as Level C. An example is the use of penicillin for pneumococcal pneumonia, for which there are no randomized trials and treatment is based on clinical experience. When recommendations at Level C are supported by historical clinical data, appropriate references (including clinical reviews) are cited if available. For issues for which sparse data are available, a survey of current practice among the clinicians on the writing committee was the basis for Level C recommendations, and no references are cited. The schema for Classification of Recommendations and Level of Evidence is summarized in Table 1, which also illustrates how the grading system provides an estimate of the size and the certainty of the treatment effect. A new addition to the ACCF/AHA methodology is a separation of the Class III recommendations to delineate whether the recommendation is determined to be of “no benefit” or associated with “harm” to the patient. In addition, in view of the increasing number of comparative effectiveness studies, comparator verbs and suggested phrases for writing recommendations for the comparative effectiveness of one treatment/strategy with respect to another for Class of Recommendation I and IIa, Level of Evidence A or B only have been added.Table 1 Applying Classification of Recommendations and Level of EvidenceTable 1 Applying Classification of Recommendations and Level of EvidenceData available from clinical trials or registries about the usefulness/efficacy in different subpopulations, such as gender, age, history of diabetes, history of prior myocardial infarction, history of heart failure, and prior aspirin use. A recommendation with Level of Evidence B or C does not imply that the recommendation is weak. Many important clinical questions addressed in the guidelines do not lend themselves to clinical trials. Even though randomized trials are not available, there may be a very clear clinical consensus that a particular test or therapy is useful or effective.†For comparative effectiveness recommendations (Class I and IIa; Level of Evidence: A and B only), studies that support the use of comparator verbs should involve direct comparisons of the treatments or strategies being evaluated.The Task Force makes every effort to avoid actual, potential, or perceived conflicts of interest that may arise as a result of relationships with industry and other entities (RWI) among the writing committee. Specifically, all members of the writing committee, as well as peer reviewers of the document, are asked to disclose all current relationships and those 24 months before initiation of the writing effort that may be perceived as relevant. All guideline recommendations require a confidential vote by the writing committee and must be approved by a consensus of the members voting. Any writing committee member who develops a new relationship with industry during his or her tenure is required to notify guideline staff in writing. These statements are reviewed by the Task Force and all members during each conference call and/or meeting of the writing committee and are updated as changes occur. For detailed information about guideline policies and procedures, please refer to the ACCF/AHA methodology and policies manual.1 Authors' and peer reviewers' relationships with industry and other entities pertinent to this guideline are disclosed in Appendixes 1 and 2, respectively. Disclosure information for the Task Force is available online at www.cardiosource.org/ACC/About-ACC/Leadership/Guidelines-and-Documents-Task-Forces.aspx. The work of the writing committee was supported exclusively by the ACCF and AHA (and other partnering organizations) without commercial support. Writing committee members volunteered their time for this effort.The ACCF/AHA practice guidelines address patient populations (and healthcare providers) residing in North America. As such, drugs that are currently unavailable in North America are discussed in the text without a specific class of recommendation. For studies performed in large numbers of subjects outside of North America, each writing committee reviews the potential impact of different practice patterns and patient populations on the treatment effect and the relevance to the ACCF/AHA target population to determine whether the findings should inform a specific recommendation.The ACCF/AHA practice guidelines are intended to assist healthcare providers in clinical decision making by describing a range of generally acceptable approaches for the diagnosis, management, and prevention of specific diseases or conditions. These practice guidelines represent a consensus of expert opinion after a thorough review of the available current scientific evidence and are intended to improve patient care. The guidelines attempt to define practices that meet the needs of most patients in most circumstances. The ultimate judgment regarding care of a particular patient must be made by the healthcare provider and patient in light of all the circumstances presented by that patient. Thus, there are situations in which deviations from these guidelines may be appropriate. Clinical decision making should consider the quality and availability of expertise in the area where care is provided. When these guidelines are used as the basis for regulatory or payer decisions, the goal should be improvement in quality of care. The Task Force recognizes that situations arise for which additional data are needed to better inform patient care; these areas will be identified within each respective guideline when appropriate.Prescribed courses of treatment in accordance with these recommendations are effective only if they are followed. Because lack of patient understanding and adherence may adversely affect outcomes, physicians and other healthcare providers should make every effort to engage the patient's active participation in prescribed medical regimens and lifestyles.The guidelines will be reviewed annually by the Task Force and considered current unless they are updated, revised, or withdrawn from distribution. The full-text guideline is e-published in the Journal of the American College of Cardiology, Circulation, and Stroke and is posted on the American College of Cardiology (www.cardiosource.org) and AHA (my.americanheart.org) World Wide Web sites.1. Introduction1.1. Methodology and Evidence ReviewThe ACCF/AHA writing committee to create the 2011 Guideline on the Management of Patients With Extracranial Carotid and Vertebral Artery Disease (ECVD) conducted a comprehensive review of the literature relevant to carotid and vertebral artery interventions through May 2010.The recommendations listed in this document are, whenever possible, evidence-based. Searches were limited to studies, reviews, and other evidence conducted in human subjects and published in English. Key search words included but were not limited to angioplasty, atherosclerosis, carotid artery disease, carotid endarterectomy (CEA), carotid revascularization, carotid stenosis, carotid stenting, carotid artery stenting (CAS), extracranial carotid artery stenosis, stroke, transient ischemic attack (TIA), and vertebral artery disease. Additional searches cross-referenced these topics with the following subtopics: acetylsalicylic acid, antiplatelet therapy, carotid artery dissection, cerebral embolism, cerebral protection, cerebrovascular disorders, complications, comorbidities, extracranial atherosclerosis, intima-media thickness, medical therapy, neurological examination, noninvasive testing, pharmacological therapy, preoperative risk, primary closure, risk factors, and vertebral artery dissection. Additionally, the committee reviewed documents related to the subject matter previously published by the ACCF and AHA (and other partnering organizations). References selected and published in this document are representative and not all-inclusive.To provide clinicians with a comprehensive set of data, whenever deemed appropriate or when published in the article, data from the clinical trial were used to calculate the absolute risk difference and number needed to treat or harm; data related to the relative treatment effects are also provided, such as odds ratio (OR), relative risk, hazard ratio (HR), or incidence rate ratio, along with confidence intervals (CIs) when available.The committee used the evidence-based methodologies developed by the Task Force and acknowledges that adjudication of the evidence was complicated by the timing of the evidence when 2 different interventions were contrasted. Despite similar study designs (eg, randomized controlled trials), research on CEA was conducted in a different era (and thus, evidence existed in the peer-reviewed literature for more time) than the more contemporary CAS trials. Because evidence is lacking in the literature to guide many aspects of the care of patients with nonatherosclerotic carotid disease and most forms of vertebral artery disease, a relatively large number of the recommendations in this document are based on consensus.The writing committee chose to limit the scope of this document to the vascular diseases themselves and not to the management of patients with acute stroke or to the detection or prevention of disease in individuals or populations at risk, which are covered in another guideline.2 The full-text guideline is based on the presumption that readers will search the document for specific advice on the management of patients with ECVD at different phases of illness. Following the typical chronology of the clinical care of patients with ECVD, the guideline is organized in sections that address the pathogenesis, epidemiology, diagnostic evaluation, and management of patients with ECVD, including prevention of recurrent ischemic events. The text, recommendations, and supporting evidence are intended to assist the diverse array of clinicians who provide care for patients with ECVD. In particular, they are designed to aid primary care clinicians, medical and surgical cardiovascular specialists, and trainees in the primary care and vascular specialties, as well as nurses and other healthcare personnel who seek clinical tools to promote the proper evaluation and management of patients with ECVD in both inpatient and outpatient settings. Application of the recommended diagnostic and therapeutic strategies, combined with careful clinical judgment, should improve diagnosis of each syndrome, enhance prevention, and decrease rates of stroke and related long-term disability and death. The ultimate goal of the guideline statement is to improve the duration and quality of life for people with ECVD.1.2. Organization of the Writing CommitteeThe writing committee to develop the 2011 ASA/ACCF/AHA/AANN/AANS/ACR/ASNR/CNS/SAIP/SCAI/SIR/SNIS/SVM/SVS Guideline on the Management of Patients With Extracranial Carotid and Vertebral Artery Disease was composed of experts in the areas of medicine, surgery, neurology, cardiology, radiology, vascular surgery, neurosurgery, neuroradiology, interventional radiology, noninvasive imaging, emergency medicine, vascular medicine, nursing, epidemiology, and biostatistics. The committee included representatives of the American Stroke Association (ASA), ACCF, AHA, American Academy of Neurology (AAN), American Association of Neuroscience Nurses (AANN), American Association of Neurological Surgeons (AANS), American College of Emergency Physicians (ACEP), American College of Radiology (ACR), American Society of Neuroradiology (ASNR), Congress of Neurological Surgeons (CNS), Society of Atherosclerosis Imaging and Prevention (SAIP), Society for Cardiovascular Angiography and Interventions (SCAI), Society of Cardiovascular Computed Tomography (SCCT), Society of Interventional Radiology (SIR), Society of NeuroInterventional Surgery (SNIS), Society for Vascular Medicine (SVM), and Society for Vascular Surgery (SVS).1.3. Document Review and ApprovalThe document was reviewed by 55 external reviewers, including individuals nominated by each of the ASA, ACCF, AHA, AANN, AANS, ACEP, American College of Physicians, ACR, ASNR, CNS, SAIP, SCAI, SCCT, SIR, SNIS, SVM, and SVS, and by individual content reviewers, including members from the ACCF Catheterization Committee, ACCF Interventional Scientific Council, ACCF Peripheral Vascular Disease Committee, ACCF Surgeons' Scientific Council, ACCF/SCAI/SVMB/SIR/ASITN Expert Consensus Document on Carotid Stenting, ACCF/AHA Peripheral Arterial Disease Guideline Writing Committee, AHA Peripheral Vascular Disease Steering Committee, AHA Stroke Leadership Committee, and individual nominees. All information on reviewers' relationships with industry and other entities was distributed to the writing committee and is published in this document (Appendix 2).This document was reviewed and approved for publication by the governing bodies of the ASA, ACCF, and AHA and endorsed by the AANN, AANS, ACR, ASNR, CNS, SAIP, SCAI, SCCT, SIR, SNIS, SVM, and SVS. The AAN affirms the value of this guideline.2. Recommendations for Duplex Ultrasonography to Evaluate Asymptomatic Patients With Known or Suspected Carotid StenosisClass IIn asymptomatic patients with known or suspected carotid stenosis, duplex ultrasonography, performed by a qualified technologist in a certified laboratory, is recommended as the initial diagnostic test to detect hemodynamically significant carotid stenosis. (Level of Evidence: C)Class IIaIt is reasonable to perform duplex ultrasonography to detect hemodynamically significant carotid stenosis in asymptomatic patients with carotid bruit. (Level of Evidence: C)It is reasonable to repeat duplex ultrasonography annually by a qualified technologist in a certified laboratory to assess the progression or regression of disease and response to therapeutic interventions in patients with atherosclerosis who have had stenosis greater than 50% detected previously. Once stability has been established over an extended period or the patient's candidacy for further intervention has changed, longer intervals or termination of surveillance may be appropriate. (Level of Evidence: C)Class IIbDuplex ultrasonography to detect hemodynamically significant carotid stenosis may be considered in asymptomatic patients with symptomatic peripheral arterial disease (PAD), coronary artery disease, or atherosclerotic aortic aneurysm, but because such patients already have an indication for medical therapy to prevent ischemic symptoms, it is unclear whether establishing the additional diagnosis of ECVD in those without carotid bruit would justify actions that affect clinical outcomes. (Level of Evidence: C)Duplex ultrasonography might be considered to detect carotid stenosis in asymptomatic patients without clinical evidence of atherosclerosis who have 2 or more of the following risk factors: hypertension, hyperlipidemia, tobacco smoking, a family history in a first-degree relative of atherosclerosis manifested before age 60 years, or a family history of ischemic stroke. However, it is unclear whether establishing a diagnosis of ECVD would justify actions that affect clinical outcomes. (Level of Evidence: C)Class III: No BenefitCarotid duplex ultrasonography is not recommended for routine screening of asymptomatic patients who have no clinical manifestations of or risk factors for atherosclerosis. (Level of Evidence: C)Carotid duplex ultrasonography is not recommended for routine evaluation of patients with neurological or psychiatric disorders unrelated to focal cerebral ischemia, such as brain tumors, familial or degenerative cerebral or motor neuron disorders, infectious and inflammatory conditions affecting the brain, psychiatric disorders, or epilepsy. (Level of Evidence: C)Routine serial imaging of the extracranial carotid arteries is not recommended for patients who have no risk factors for development of atherosclerotic carotid disease and no disease evident on initial vascular testing. (Level of Evidence: C)3. Recommendations for Diagnostic Testing in Patients With Symptoms or Signs of Extracranial Carotid Artery DiseaseClass IThe initial evaluation of patients with transient retinal or hemispheric neurological symptoms of possible ischemic origin should include noninvasive imaging for the detection of ECVD. (Level of Evidence: C)Duplex ultrasonography is recommended to detect carotid stenosis in patients who develop focal neurological symptoms corresponding to the territory supplied by the left or right internal carotid artery. (Level of Evidence: C)In patients with acute, focal ischemic neurological symptoms corresponding to the territory supplied by the left or right internal carotid artery, magnetic resonance angiography (MRA) or computed tomography angiography (CTA) is indicated to detect carotid stenosis when sonography either cannot be obtained or yields equivocal or otherwise no